Known biological processes for producing an .alpha.-hydroxyamide include a process comprising reacting lactonitrile, hydroxyacetonitrile, .alpha.-hydroxymethylthiobutyronitrile etc. with a microorganism belonging to the genus Bacillus, Bacteridium, Micrococcus or Brevibacterium to obtain a corresponding amide as disclosed in JP-B-62-21519 (corresponding to U.S. Pat. No. 4,001,081) (the term "JP-B" as used herein means an "examined published Japanese patent application"). It is also reported in Grant, D. J. W., Antonie van Leeuwenhoek; J. Microbiol. Serol. Vol. 39, p. 273 (1973) that hydrolysis of lactonitrile by the action of a microorganism belonging to the genus Corynebacterium to produce lactic acid involves accumulation of lactamide as an intermediate.
Known biological processes for producing an .alpha.-hydroxy acid include a process for obtaining glycolic acid, lactic acid, .alpha.-hydroxyisobutyric acid etc. from the corresponding .alpha.-hydroxynitrile by the action of a microorganism of the genus Corynebacterium (see JP-A-61-56086, the term "JP-A" as used herein means an "unexamined published Japanese patent application"), a process for obtaining lactic acid, glycolic acid etc. from the corresponding .alpha.-hydroxynitrile by using a microorganism of the genus Bacillus, Bacteridium, Micrococcus or Brevibacterium (see JP-B-58-15120, corresponding to U.S. Pat. No. 3,940,316), a process for obtaining lactic acid, .alpha.-hydroxyisobutyric acid, mandelic acid, .alpha.-hydroxybutyric acid, .alpha.-hydroxyvaleric acid, .alpha.-hydroxy-.alpha.-phenylpropionic acid, .alpha.-hydroxy-.alpha.-(p-isobutylphenyl)propionic acid etc. from the corresponding .alpha.-hydroxynitrile by using a microorganism of the genus Pseudomonas, Arthrobacter, Aspergillus, Penicillium, Cochliobolus or Fusarium (see JP-A-63-222696) and a process for obtaining .alpha.-hydroxy-.beta.,.beta.-dimethyl-.gamma.-butyrolactone from the corresponding .alpha.-hydroxynitrile by using a microorganism of the genus Arthrobacter. Aspergillus, Bacillus, Bacteridium, Brevibacterium, Cochliobolus, Corynebacterium. Micrococcus, Nocardia. Penicillium, Pseudomonas or Fusarium (see JP-A-64-10996).
It is known, however, that an .alpha.-hydroxynitrile is, more or less, partially dissociated into the corresponding aldehyde and hydrogen cyanide in a polar solvent as taught in V. Okano et al., J. Am. Chem. Soc., Vol. 98, p. 4201 (1976). Since an aldehyde generally is bound to proteins to deactivate enzymes as described in G. E. Means et al. (ed.), Chemical Modification of Proteins, p. 125, Holden-Day (1971), enzymatic hydration or hydrolysis of an .alpha.-hydroxynitrile is accompanied with the problem that the enzyme is deactivated in a short time. It therefore has been difficult to obtain an .alpha.-hydroxyamide or an .alpha.-hydroxy acid in high concentration with high productivity.